With an increase in the functions of the user equipments, the speed of radio communication with the base station has increased. In recent years, in a 3GPP LTE standard, LTE Release (hereinafter, referred to as Rel) 10 (a downstream speed of 1 Gbps and an upstream speed of 500 Mbps), which is called an LTE-Advanced system, with a higher processing speed than that of LTE Rel 8 (a downstream speed of 300 Mbps and an upstream speed of 75 Mbps) has been put to practical use.
In the LTE-Advanced standard, a “carrier aggregation” (hereinafter, referred to as CA) technique which treats the carrier used in LTE Rel 8 as a component carrier (hereinafter, referred to as CC) unit and uses up to five component carriers at the same time to communicate with one user equipment has been used to expand a communication bandwidth and to increase the processing speed.
In contrast, in the LTE test system according to the related art, a baseband test signal (orthogonal components I and Q) corresponding to one carrier which is used for communication with the device under test is generated, a signal which is quadrature-modulated with the test signal is frequency-converted into a signal in a communication frequency band, and the converted signal is used.
A great number of parameters are needed in order to generate the test signal and the tester sets the parameters one by one. Therefore, this structure is inefficient.
Therefore, for example, in 3GPP TS36.141 (BS test standard) which is a base station test standard, combinations of plural types of test models for specifying test conditions and a channel band of carriers required to generate test signals for each test model are defined in advance, parameter information (parameter file) is stored in a storage unit in advance, and the tester selects the test model and the channel band to generate waveform data of the test signal for performing the selected test model in the designated channel bandwidth.
As an example of the test system, Patent Document 1 discloses a system which generates a test signal for testing a user equipment, converts the signal which is quadrature-modulated with the test signal into a signal in the communication frequency band, and outputs the converted signal.